1. Factor Markets: Introduction and Factor Demand
Micro:
Econ: 33 69
Module
Factor Markets: Introduction and Factor Demand
KRUGMAN'S
MICROECONOMICS for AP*
Margaret Ray and David Anderson

2. What you will learn in this Module:
What are the factors of production?
How do factor markets determine the factor distribution of income?
How is the demand for a factor of production determined?
The purpose of this module is to demonstrate that the demand for a factor of production (like labor, capital, or land) is derived from the demand for the goods that are produced by those factors. The value of the marginal product curve is shown to serve as the demand curve for a factor of production and the profit maximizing quantity of a factor hired is at the point where the VMP of the last unit is equal to the marginal cost of hiring that unit of a factor.

3. Vocabulary
Factor [n or v] the important part of something, to find the….
What are the factors of a sexy guy/girl in China?
Derive [v] to get from
Derive the factors for (X2+2X+1)
Economists typically discuss four factors of production.
Note: students may also see these identified as “inputs” or “resources” on the AP exam.
Labor: the work done by humans.
Land: resources provided by nature.
Capital: physical capital such as tools, machinery and factories, plus human capital such as education and training.
Entrepreneurship: the talent for taking risks to bring together resources for innovative production
Land, labor, and capital can be exchanged in markets with suppliers and demanders. In these markets, equilibrium prices and quantities are established.
Entrepreneurship is not as tangible or quantifiable as the others, and is not easily identified in the framework of a market, but it is nonetheless quite important.

4. 4 Factors [Resources] of Production
Labor
Land
Capital: 2 Types
Physical Capital: Manufactured resources such as equipment, buildings, tools, etc
Human Capital: improvement in labor due to education and knowledge
Entrepreneurship [n] the ability or desire to start a business, to take a risk
Economists typically discuss four factors of production.
Note: students may also see these identified as “inputs” or “resources” on the AP exam.
Labor: the work done by humans.
Land: resources provided by nature.
Capital: physical capital such as tools, machinery and factories, plus human capital such as education and training.
Entrepreneurship: the talent for taking risks to bring together resources for innovative production
Land, labor, and capital can be exchanged in markets with suppliers and demanders. In these markets, equilibrium prices and quantities are established.
Entrepreneurship is not as tangible or quantifiable as the others, and is not easily identified in the framework of a market, but it is nonetheless quite important.

5. Factor Distribution of Income in US
Factor Prices
Factor Distribution of Income in US
Factor prices allocate resources among producers
The demand for a factor of production is a derived demand
Derived Demand: demand for the factor is created by the demand for the firm’s output Ex: Demand for doctors created from the demand for health care.
Derived demand – the demand for a factor is derived from a firm’s output choice.
The demand for labor, and other factors of production, is a derived demand. For example, the demand for nurses is derived from the demand for the services that nurses provide. As the US population ages, the demand for medical care, which certainly includes nursing services, rises and thus the demand for nurses rises.
Imagine all of the income earned in the US as a pie chart. The pie is divided into four slices that account for the %of income earned by each of the four factors of production.
When factor prices change, the distribution of factor income changes.
Suppose that wages and salaries have been rising. All else equal, the share of national income that goes to the labor factor would increase. Labor’s slice of the pie would be getting bigger.

6. Factor Distribution of Income in US
Factor Prices
Factor Distribution of Income in US
Economists care about how much household income comes from each type of input. This is called factor distribution of income.
In the USA, 70% or more of the income comes from wages paid to laborers.
What does this mean about:
A) the ownership of capital
B) the value of human capital
Derived demand – the demand for a factor is derived from a firm’s output choice.
The demand for labor, and other factors of production, is a derived demand. For example, the demand for nurses is derived from the demand for the services that nurses provide. As the US population ages, the demand for medical care, which certainly includes nursing services, rises and thus the demand for nurses rises.
Imagine all of the income earned in the US as a pie chart. The pie is divided into four slices that account for the %of income earned by each of the four factors of production.
When factor prices change, the distribution of factor income changes.
Suppose that wages and salaries have been rising. All else equal, the share of national income that goes to the labor factor would increase. Labor’s slice of the pie would be getting bigger.

7. Marginal Productivity and Factor Demand
Marginal product (MP) is the additional output produced as a result of hiring an additional unit of a factor of production. For example, MPL = additional output from hiring an additional worker.
How can we use the idea of marginal product to interpret when a firm should hire another worker?
MPL tells us how much additional output the next worker brings to the firm, but how many dollars will the worker’s efforts bring into the firm?
We need to consider the price of the product.
The total monetary benefit of hiring each worker is called the value of the marginal product VMPL.
VMPL = (Price of the output)*MPL
Hiring workers, like so many other decisions in microeconomics, requires a comparison of the marginal benefit of the next worker (the VMPL) to the marginal cost of the next worker. We assume for now that each unit of labor can be hired at a constant wage W.
Hire a worker if: VMPL >= W.
Never hire a worker if: VMPL < W.
Stop hiring workers up to the point where: VMPL = W.
This is the profit-maximizing hiring decision for ANY factor of production. The last unit of any factor is hired when the value of its marginal product is exactly equal to the marginal cost of hiring it.
The Law of Demand also applies in factor markets. As the price of a factor increases, firms hire less of that factor (and as the price of a factor falls, firms hire less of that factor).
The VMPL curve serves as the demand for labor. For any factor, the VMP curve serves as the demand curve for that factor of production.

8. Figure 69.1 from text

9. Figure 69.2 from text

10. Marginal Productivity and Factor Demand
What is the formula for profit?
The value of the marginal product (VMP) is the value of the additional output produced as a result of hiring an additional unit of a factor. For example, for labor, VMPL = MPL x P.
The VMP curve is the demand curve for a factor (with a perfectly competitive factor market).
MPL tells us how much additional output the next worker brings to the firm, but how many dollars will the worker’s efforts bring into the firm?
We need to consider the price of the product.
The total monetary benefit of hiring each worker is called the value of the marginal product VMPL.
VMPL = (Price of the output)*MPL
Hiring workers, like so many other decisions in microeconomics, requires a comparison of the marginal benefit of the next worker (the VMPL) to the marginal cost of the next worker. We assume for now that each unit of labor can be hired at a constant wage W.
Hire a worker if: VMPL >= W.
Never hire a worker if: VMPL < W.
Stop hiring workers up to the point where: VMPL = W.
This is the profit-maximizing hiring decision for ANY factor of production. The last unit of any factor is hired when the value of its marginal product is exactly equal to the marginal cost of hiring it.
The Law of Demand also applies in factor markets. As the price of a factor increases, firms hire less of that factor (and as the price of a factor falls, firms hire less of that factor).
The VMPL curve serves as the demand for labor. For any factor, the VMP curve serves as the demand curve for that factor of production.

11. Marginal Productivity and Factor Demand
A firm should employ workers until the point
VMPL = Wage Rate
This rule holds true for all factors of production. Profit maximizing firms will keep adding more units of each factor of production until the value of the marginal product of the last unit employed is equal to the factors price
MPL tells us how much additional output the next worker brings to the firm, but how many dollars will the worker’s efforts bring into the firm?
We need to consider the price of the product.
The total monetary benefit of hiring each worker is called the value of the marginal product VMPL.
VMPL = (Price of the output)*MPL
Hiring workers, like so many other decisions in microeconomics, requires a comparison of the marginal benefit of the next worker (the VMPL) to the marginal cost of the next worker. We assume for now that each unit of labor can be hired at a constant wage W.
Hire a worker if: VMPL >= W.
Never hire a worker if: VMPL < W.
Stop hiring workers up to the point where: VMPL = W.
This is the profit-maximizing hiring decision for ANY factor of production. The last unit of any factor is hired when the value of its marginal product is exactly equal to the marginal cost of hiring it.
The Law of Demand also applies in factor markets. As the price of a factor increases, firms hire less of that factor (and as the price of a factor falls, firms hire less of that factor).
The VMPL curve serves as the demand for labor. For any factor, the VMP curve serves as the demand curve for that factor of production.

12. Price of wheat = $20 per bushel At a wage rate of $200 what is the profit maximizing point?

13. Profit Maximizing Point: VMPL=W (Point A)

14. What Causes the Factor Demand Curve to Shift?
Changes in the prices of goods
Changes in the supply of other factors
Changes in technology
VMP = D
W and VMPL
Generally there are three external variables that will shift the demand curve for a factor. Each of these changes some aspect of VMP.
1. Changes in the prices of goods
Remember that the price of the product is an important part of the VMP.
If the price rises, even if the factor is not more productive, the VMP of the factor will rise.
2. Changes in the supply of other factors
If labor is paired with capital (tools), the labor is usually more productive. If capital (or land) is more plentiful, usually the marginal product of each unit of labor is higher, the VMPL curve shifts outward, and more units of labor are hired at all wages.
3. Changes in technology
Better technology increases production across the board. In some cases, technology replaces certain factors (like machines replacing labor), but in the long run better technology allows a nation’s labor force to be more productive and the demand for labor shifts outward.
Units of Labor

15. Mini-project
You own an apple farm. A scientist invents a new robot that can work on the farm.
A) the robot helps the workers
B) the robot replaces the workers
Choose situation A or B.
Explain the changes to the VMP curve for:
Labor
Land
Physical capital
Human capital
Generally there are three external variables that will shift the demand curve for a factor. Each of these changes some aspect of VMP.
1. Changes in the prices of goods
Remember that the price of the product is an important part of the VMP.
If the price rises, even if the factor is not more productive, the VMP of the factor will rise.
2. Changes in the supply of other factors
If labor is paired with capital (tools), the labor is usually more productive. If capital (or land) is more plentiful, usually the marginal product of each unit of labor is higher, the VMPL curve shifts outward, and more units of labor are hired at all wages.
3. Changes in technology
Better technology increases production across the board. In some cases, technology replaces certain factors (like machines replacing labor), but in the long run better technology allows a nation’s labor force to be more productive and the demand for labor shifts outward.

16. Summary Derived Demand Labor demand = MPL x P
Demand shifts from changes in:
Price
Supply of other factors
Technology
The supply of land is upward sloping, but nearly vertical, or very inelastic. After all, there are only so many square miles (or kilometers) of usable land in a nation. If the rental rate of farmland were to increase, it is possible to convert land from one non-farm use to farm use, but it’s costly to do.
The supply of capital is also upward sloping, but much less steep, or very elastic. If the rental rate on capital rises, firms that supply capital will simply operate their factories longer and create more capital machines.
Note: in a macro course, students learn that the funds for new investment in capital machinery and new construction come from savers. If the rate of return on savings rises, households will save more money, thus greasing the wheels of new investment spending.